Scaling Geothermal for Reliable Baseload Power

Reno, Nevada [RenewableEnergyAccess.com]
Geothermal is the most reliable form of renewable baseload power and given the proper financial support from the private sector -- and favorable policies from government -- it will become a viable alternative to coal, natural gas and nuclear, according to speakers at the Geothermal Resource Council's annual meeting in Reno, Nevada earlier this week.

"We spend a lot of time talking about the resource that beams down from space or blows over us. But we don't spend enough time looking at our very abundant terrestrial geothermal resources that will provide reliable, renewable baseload power."
-- Andy Karsner, Assistant Secretary for Energy Efficiency and Renewable Energy, DOE

The meeting, held in conjunction with the Geothermal Energy Association (GEA) trade show, drew an estimated 2,000 people and over 50 exhibitors ranging from project developers to investment bankers.

While geothermal currently makes up less than 0.5% of the nation's energy supply, speakers at the opening session were optimistic about the future of the industry. They encouraged attendees to continue working on the goal of bringing geothermal to cost parity with fossil fuels and to gain the same level of attention that other forms of renewable energy have received in recent years.

But getting there will require a focused national effort to formulate policies that level the playing field for geothermal energy—and allow the industry to access critical financial resources from the government and private sectors.

"We spend a lot of time talking about the resource that beams down from space or blows over us. But we don't spend enough time looking at our very abundant terrestrial geothermal resources that will provide reliable, renewable baseload power," said Andy Karsner, Assistant Secretary for Energy Efficiency and Renewable Energy at the U.S. Department of Energy (DOE).

According to a recent report from MIT, "a cumulative capacity of more than 100,000 MW from enhanced geothermal systems (EGS) can be achieved in the United States within 50 years with a modest, multiyear federal investment for R&D in several field projects in the United States." Currently only 3,000 MW—or 3% of that potential—is installed in the U.S.

In May 2007, the GEA issued a report that identified 74 new geothermal power projects in Alaska, Arizona, California, Hawaii, Idaho, New Mexico, Nevada, Oregon, Texas, Utah, Washington and Wyoming. According to the GEA, these projects will double U.S. geothermal power capacity to almost 6,000 MW.

Another report on the international market, which the GEA released in April, identified 40 countries with geothermal power development underway-and projected a 50% growth in power production worldwide by2010.

"We have seen dramatic new interest in the geothermal industry," said Karl Gawell, executive director of the GEA. "That is translating into many new geothermal projects in the U.S. and around the world."

The MIT report, which was authored on behalf of the DOE, also found that "EGS is one of the few renewable energy resources that can provide continuous baseload power with minimal visual and other environmental impacts." The study concluded that "geothermal systems have a small footprint and virtually no emissions, including carbon dioxide. Geothermal energy has significant baseload potential, requires no storage, and, thus, it complements other renewables-solar (CSP and PV), wind, hydropower-in a lower carbon energy future."

However, as is the case with all the other renewable energy technologies, the geothermal industry faces many formidable challenges before the resource can be fully exploited. Because projects are so capital intensive and require a relatively long timeframe for completion, developers can find it difficult to secure up-front financing for projects.

In addition, the science for identifying the exact location and capacity of a resource still requires further development.

Due to the high cost of drilling, it is critical for developers to strike the resource on the first try. Because of this the geothermal industry is now looking to the oil and natural gas industry for resource assessment tools and advanced drilling equipment that will allow for speedier, more cost-effective development. But with oil prices hovering around $80 per barrel, there is often competition between the geothermal and fossil fuel industries for such equipment, which can significantly slow a project.

Getting consistent support from policy makers and regulators has also proven to be difficult for the industry. Loan guarantees, risk insurance and long-term production tax credits are needed to encourage more large-scale development and keep the industry thriving. The industry has been pushing hard to gain these incentives in the energy bill currently in Congress.

In addition they are also requesting stronger support from the DOE, which considered scrapping its geothermal program last year. Although Assistant Secretary Karsner did not mention that fact, he did acknowledge that more support from the government is needed and also asked the industry to step forward and demonstrate the leadership required to get the job done.

"Is the Department of Energy up to the task of providing meaningful assistance to your industry? I hope so. But in the meantime, your industry needs to tell the government how we can make a difference," said Karsner.

Oliver Strube is publisher and co-founder of RenewableEnergyAccess.com. Stephen Lacey is editor and host of the Inside Renewable Energy podcast.

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15 Comments

We have in U.S. more of 20 well drilling co. capable to drill geothermal wells. Oil at $90.00 pb do not impact the cost of producing electricity, the 50% of power generation plants in U.S. use coal. Before invest in geothermal energy to generate steam we have W-T-E waste to energy landfill gasification can be use to generate power, using steam turbine.

One of the major roadblocks to geothermal is the large number and cost of externalities (power transfer stations, cabling, wires, transmission lines, labor, support structures, etc.) and another roadblock is the land-use issues that inevitably arise.
Solution: Find a suitable site (West Texas or Southern California look to be ideal) and construct a triple decker all natural power plant that has Ehanced Geothermal under the surface, PV or CSP covering the surface and wind turbines making energy from the air. Adding hydro or biofuel fields are also a possibility depending on the site. This was we can solve the land use issue by making the most out of the land without upsetting anti-large scale development environmentalists while also eliminating a great deal of the costs by combining the externalities so that they are focused on one site vs. installing, paying, and maintaining them three times for an EGS site one place, a solar plant in another, and a wind farm in yet another.

Rob, the focus of this article appears to be "hot" geothermal alone, which in fact is used mostly as a source of electricity and sometimes additionally used for process heat or district heating. You seem to be referring to geoexchange heat pumps or more technically "ground source heat pumps" that are used to heat AND cool buildings. The "hot" geothermal with current technology is usable in areas where there is sufficient heat flow and rock permeability (in the US mostly parts of the West, California, Nevada, Oregon, Texas oil fields) The new EGS technology promises to expand the geographical range of "hot" geothermal.

Ground source heat pumps or geoexchange, which is a space heating and cooling technology, can be used in almost any location because it is using the temperature, and heat conductivity of the upper layers of soil and rock that come mostly from the sun and not so much the magmatic heat of the mantle and core of the earth.

There are many questions still to be answered about drilling for geothermal sites, especially the deep hole sites (10km or more). The big study of Nevada and California geothermal, noted that at only 4km, the cost of drilling alone would run the price to $6/installed watt. Ten kilometers could only be worse, when we need $1/watt to compete with coal.

I also wonder about what's down there at "hot rock" level. It could be a mistake to believe that what comes up the second hole will be "clean" steam. Depending on the mineral constitution at the bottom of the hole, it could come back highly corrosive, etc.

In response to the above comments, it should be noted that renewable energy has been widely interpreted as sources of energy that are renewable within the scope of a human life time.

As far as global impact, geothermal technology that is currently employed is not terribly likely to cause widespread damage. What is at danger however is that sources of geothermal heat can be expended over a period of time. Iceland which utilizes geothermal for much of its electrical capacity estimates that current wells have a lifetime of 100-200 years.

There are other local impacts such as emissions and land destabilization but it remains unlikely that there will be same level of impact as global warming. I have seen no literature suggesting cataclysmic damages.

Steam will be spilling from efforts of drilling for heat sources far down below,
Recoup all expenses with hot rock defenses will give its investors the go,
Oil-gas sets the paces to start on the races for treasure that's yearning to be found,
With equipment for seeking the heat that is leaking where volcanic vents abound.

No pollution in sight as with coal in plight Geothermal to give clean power,
A level to attain where ground steam will be the main source of heat for each megawatt hour,
Geothermal is waiting without our debating as to whether or not we are willing.
Let us come to our senses, take care of expenses up front needed in deep drilling,

Investors take heed Geothermal's the seed to be planted for harvesting money,
If wealth is the goal then look down and behold so much energy its not funny,
As the years roll by we will be sad and sigh if we don't make an effort, not just yearning,
For the steam from the Earth means a turbine rebirth of power without coal burning.

Our government's task is to help if we ask for assistance with law and regulation,
Our officials must see that democracy is for service to all in our nation,
For the question at hand is to find for our land sustainable, pure energy,
Steady sources of power will blessings on us shower for our countries security.

Mr. Peters calls for serious discussion of the long-term environmental impacts associated with geothermal energy. Fine. Just don't stop development. As it is, thinking seven generations ahead is a reach.
Serious discussion notwithstanding, we won't "know" the impacts unless and until we move forward. We already know, or can reasonably foretell the consequences associated with increased reliance upon both fossil fuels, and nuclear power.
With regard to the latter, we are already fated to secure both existing and new power plants, and the toxic waste therefrom, for millenia to come.
Here too, build more. What difference does another 50 or 100 years of nuclear power matter, when added to the far end of a 10,000 year storage and security problem...?

Apropos of Mr. Peter's raises a number of philosophical and semantic questions with his comments on geothermal energy. All energy resources in the Universe are essentially finite, including our nearest star, which will eventually run out of its Hydrogen fuel. Heat leakage from the earth into outer space is about 42 Million MW and, though not in the same class as Sol, is certainly humongous. The earth's crust occupies 2% of its volume but accounts for 20% of the geothermal heat. Contrary to popular opinion, most of the geothermal energy occurring in the crust is radiogenic in nature, resulting from fission of radioactive isotopes in the lithospehre and the asthenosphere. This is mass transformational energy as any student of Einstein will vouch and therefore throws up the question whether nuclear energy is renewable. If Solar energy, powered by nuclear reactions, is classified as "renewable", geothermal energy by extension is also "renewable".

Do we understand the long-term impacts of using geothermal energy? Will development at huge scales interfere with planetary processes? If this sounds like a nutty thing to even ask, imagine telling a British industrialist 170 years ago not to burn coal because he might change the weather.

I think using geothermal energy may be a necessary response to climate change. I would like to see more discussion of potential effects of massive scale geothermal energy extraction, and I would like to have it stop being referred to as "renewable."

Our system of interest is Earth. Any energy source restricted to that system (the planet) is locally finite and, by definition, not renewable. Renewable energy is, therefore, energy whose source is extraterrestrial, including the sun and its derivatives (wind, waves, hydro-dams...).

It may seem a semantic distraction, but I think the language matters.

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I am a reporter with ClimateProgress.org, a blog published by the Center for American Progress. I am former editor and producer for RenewableEnergyWorld.com, where I contributed stories and hosted the Inside Renewable Energy Podcast. Keep...